[PATCH 37/58] mtd: rawnand: meson: retain open-handle state on removal

[James Hilliard]

Keep chip metadata and controller storage alive until the final MTD
reference is released. Unregister and disconnect each published chip
before releasing the resources used by its hardware operations.

The deferred detach callback only frees heap-allocated transfer buffers.

Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
---
 drivers/mtd/nand/raw/meson_nand.c | 55 +++++++++++++++++++++++++++------------
 1 file changed, 39 insertions(+), 16 deletions(-)

diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
index b8834aa96e81..4f33ea7a1b4d 100644
--- a/drivers/mtd/nand/raw/meson_nand.c
+++ b/drivers/mtd/nand/raw/meson_nand.c
@@ -1381,6 +1381,11 @@ static const struct nand_controller_ops meson_nand_controller_ops = {
 	.exec_op = meson_nfc_exec_op,
 };
 
+static void meson_nfc_nand_release(struct nand_chip *nand)
+{
+	kfree(to_meson_nand(nand));
+}
+
 static int
 meson_nfc_nand_chip_init(struct device *dev,
 			 struct meson_nfc *nfc, struct device_node *np)
@@ -1398,8 +1403,7 @@ meson_nfc_nand_chip_init(struct device *dev,
 		return -EINVAL;
 	}
 
-	meson_chip = devm_kzalloc(dev, struct_size(meson_chip, sels, nsels),
-				  GFP_KERNEL);
+	meson_chip = kzalloc(struct_size(meson_chip, sels, nsels), GFP_KERNEL);
 	if (!meson_chip)
 		return -ENOMEM;
 
@@ -1410,12 +1414,13 @@ meson_nfc_nand_chip_init(struct device *dev,
 		if (ret) {
 			dev_err(dev, "could not retrieve register property: %d\n",
 				ret);
-			return ret;
+			goto free_chip;
 		}
 
 		if (test_and_set_bit(tmp, &nfc->assigned_cs)) {
 			dev_err(dev, "CS %d already assigned\n", tmp);
-			return -EINVAL;
+			ret = -EINVAL;
+			goto free_chip;
 		}
 	}
 
@@ -1434,14 +1439,16 @@ meson_nfc_nand_chip_init(struct device *dev,
 	if (ret == -EINVAL)
 		nfc->no_rb_pin = true;
 	else if (ret)
-		return ret;
+		goto free_chip;
 
-	if (nand_rb_val)
-		return -EINVAL;
+	if (nand_rb_val) {
+		ret = -EINVAL;
+		goto free_chip;
+	}
 
 	ret = nand_scan(nand, nsels);
 	if (ret)
-		return ret;
+		goto free_chip;
 
 	if (nand->options & NAND_IS_BOOT_MEDIUM) {
 		ret = of_property_read_u32(np, "amlogic,boot-pages",
@@ -1449,8 +1456,7 @@ meson_nfc_nand_chip_init(struct device *dev,
 		if (ret) {
 			dev_err(dev, "could not retrieve 'amlogic,boot-pages' property: %d",
 				ret);
-			nand_cleanup(nand);
-			return ret;
+			goto cleanup_nand;
 		}
 
 		ret = of_property_read_u32(np, "amlogic,boot-page-step",
@@ -1458,21 +1464,30 @@ meson_nfc_nand_chip_init(struct device *dev,
 		if (ret) {
 			dev_err(dev, "could not retrieve 'amlogic,boot-page-step' property: %d",
 				ret);
-			nand_cleanup(nand);
-			return ret;
+			goto cleanup_nand;
 		}
 	}
 
+	ret = nand_set_release(nand, meson_nfc_nand_release);
+	if (ret)
+		goto cleanup_nand;
 	ret = mtd_device_register(mtd, NULL, 0);
 	if (ret) {
 		dev_err(dev, "failed to register MTD device: %d\n", ret);
-		nand_cleanup(nand);
+		nand_disconnect(nand);
+		mtd_put_master(mtd);
 		return ret;
 	}
 
 	list_add_tail(&meson_chip->node, &nfc->chips);
 
 	return 0;
+
+cleanup_nand:
+	nand_cleanup(nand);
+free_chip:
+	kfree(meson_chip);
+	return ret;
 }
 
 static void meson_nfc_nand_chips_cleanup(struct meson_nfc *nfc)
@@ -1486,8 +1501,9 @@ static void meson_nfc_nand_chips_cleanup(struct meson_nfc *nfc)
 		mtd = nand_to_mtd(&meson_chip->nand);
 		WARN_ON(mtd_device_unregister(mtd));
 
-		nand_cleanup(&meson_chip->nand);
+		nand_disconnect(&meson_chip->nand);
 		list_del(&meson_chip->node);
+		mtd_put_master(mtd);
 	}
 }
 
@@ -1544,21 +1560,28 @@ static const struct of_device_id meson_nfc_id_table[] = {
 };
 MODULE_DEVICE_TABLE(of, meson_nfc_id_table);
 
+static void meson_nfc_release(struct nand_controller *controller)
+{
+	kfree(container_of(controller, struct meson_nfc, controller));
+}
+
 static int meson_nfc_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct meson_nfc *nfc;
 	int ret, irq;
 
-	nfc = devm_kzalloc(dev, sizeof(*nfc), GFP_KERNEL);
+	nfc = kzalloc_obj(*nfc);
 	if (!nfc)
 		return -ENOMEM;
+	ret = devm_nand_controller_init(dev, &nfc->controller, meson_nfc_release);
+	if (ret)
+		return ret;
 
 	nfc->data = of_device_get_match_data(&pdev->dev);
 	if (!nfc->data)
 		return -ENODEV;
 
-	nand_controller_init(&nfc->controller);
 	INIT_LIST_HEAD(&nfc->chips);
 	init_completion(&nfc->completion);
 

-- 
2.53.0